Implementation of Self Attention Guidance in webui

https://arxiv.org/abs/2210.00939

Additional setup requirements after installation:

For AUTOMATIC1111 webui:

at commit 22bcc7be

run the following command in root directory stable-diffusion-webui/:

git apply --ignore-whitespace extensions/sd_webui_SAG/automatic1111-CFGDenoiser-and-script_callbacks-mod-for-SAG.patch

For vladmandic webui:

No longer requires patching after commit cb465b1 since required changes have been merged to upstream.

Demos: